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Associations between renal functions and exposure of arsenic and polycyclic aromatic hydrocarbon in adults living near a petrochemical complex
2020
Yuan, Tzu-Hsuen | Ke, Deng-Yuan | Wang, Joyce En-Hua | Chan, Chang-Chuan
The understanding for the impact of petrochemical pollutants exposure on renal functions is limited.Our study examined the associations between renal functions and pollutants exposure in adult residents living in the vicinity of a petrochemical industry.We recruited 2069 adult residents near a big petrochemical complex in Taiwan in 2009–2012, and they were categorized into high exposure (HE) and low exposure (LE) groups based on their address to source by 10 km radius. Study subjects were measured the urinary levels of arsenic, cadmium, mercury, thallium, and 1-hydroxypyrene (1-OHP). The estimated glomerular filtration rate (eGFR) was calculated using the Taiwanese Chronic Kidney Disease Epidemiology Collaboration equation, and the chronic kidney disease (CKD) prevalence and risks were defined according to KDIGO 2012 guidelines. Adjusted generalized linear and logistic regression models were applied to evaluate the associations between petrochemical exposure and renal functions.Subjects in the HE areas had significantly lower eGFR, higher CKD prevalence, and higher levels of urinary arsenic, cadmium, mercury, thallium and 1-OHP. The closer to complex and high exposure group of study subjects were significantly associated with the decrease in eGFR, higher ORs for CKD and high-intermediate risk of CKD. In addition, the study subjects who had two-fold urinary arsenic and 1-OHP levels were significantly with decreased 0.68 and 0.49 ml/min/1.73 m2 of eGFR, respectively.Residing closer and higher arsenic and polycyclic aromatic hydrocarbon exposure were associated with the renal impairment and risks of CKD among the residential population near the petrochemical industry.
Afficher plus [+] Moins [-]CircRNA104250 and lncRNAuc001.dgp.1 promote the PM2.5-induced inflammatory response by co-targeting miR-3607-5p in BEAS-2B cells
2020
Li, Xin | Jia, Yangyang | Nan, Aruo | Zhang, Nan | Zhou, Hanyu | Chen, Lijian | Pan, Xiujiao | Qiu, Miaoyun | Zhu, Jialu | Zhang, Han | Ling, Yihui | Jiang, Yiguo
Long-term exposure to particulate matter 2.5 (PM₂.₅) is closely related to the occurrence and development of airway inflammation. Exploration of the role of PM₂.₅ in inflammation is the first step towards clarifying the harmful effects of particulate pollution. However, the molecular mechanisms underlying PM₂.₅-induced airway inflammation are yet to be fully established. In this study, we focused on the specific roles of non-coding RNAs (ncRNAs) in PM₂.₅-induced airway inflammation. In a human bronchial epithelial cell line, BEAS-2B, PM₂.₅ at a concentration of 75 μg/mL induced the inflammatory response. Microarray and quantitative real-time polymerase chain reaction (qRT-PCR) analyses revealed significant upregulation of circRNA104250 and lncRNAuc001.dgp.1 during the PM₂.₅-induced inflammatory response in this cell line. Data from functional analyses further showed that both molecules promote an inflammatory response. CircRNA104250 and lncRNAuc001.dgp.1 target miR-3607-5p and affect expression of interleukin 1 receptor 1 (IL1R1), which influences the nuclear factor κB (NF-κB) signaling pathway. In summary, we have uncovered an underlying mechanism of airway inflammation by PM₂.₅ involving regulation of ncRNA for the first time, which provides further insights into the toxicological effects of PM₂.₅.
Afficher plus [+] Moins [-]Effects of the leaf functional traits of coniferous and broadleaved trees in subtropical monsoon regions on PM2.5 dry deposition velocities
2020
Zhang, Xuyi | Lyu, Junyao | Han, Yujie | Sun, Ningxiao | Sun, Wen | Li, Jinman | Liu, Chunjiang | Yin, Shan
Plants can intercept airborne particulate matter through deposition. Different types of plants exhibit different functional leaf traits, which can affect the dry deposition velocity (Vd). However, the most crucial leaf traits of coniferous and broadleaved trees remain unidentified. In this study, we selected 18 typical plants from the subtropical monsoon regions, where PM₂.₅ (fine particulate matter with a diameter of ≤2.5 μm) concentrations are relatively high, and classified them into coniferous and broadleaved categories. Subsequently, we analyzed the relationships between Vd and leaf surface free energy (SFE), single leaf area (LAₛ), surface roughness (SR), specific leaf area (SLA), epicuticular wax content (EWC), and width-to-length ratio (W/L). The results indicated that most coniferous trees exhibited a high Vd. The correlation analysis revealed that SFE, SR, LAₛ, and W/L were the key factors that affected the Vd of all the tested species. SFE and SLA had the strongest influence on the Vd of broadleaved trees, whereas LAₛ and SLA had the strongest effect on that of coniferous trees. Most coniferous trees had a high SLA, which can reduce water loss and hinder particle deposition. However, the stiff leaves of coniferous trees fluttered less, resulting in a larger leaf area that enhanced the capture efficiency. The leaf structure of broadleaved trees is more flexible, resulting in erratic flutter, which may impede deposition and lead to high resuspension. Coniferous and broadleaved trees may have different dominant leaf traits that affect particle deposition.
Afficher plus [+] Moins [-]Microalgal-based biopolymer for nano- and microplastic removal: a possible biosolution for wastewater treatment
2020
Cunha, César | Silva, Laura | Paulo, Jorge | Faria, Marisa | Nogueira, Natacha | Cordeiro, Nereida
The increasing water pollution caused by the presence of nano- and microplastics has shown a need to pursue solutions to remediate this problem. In this work, an extracellular polymeric substance (EPS) producing freshwater Cyanothece sp. strain was exposed to nano- and microplastics. The bioflocculant capacity of the biopolymer produced was evaluated. The influence of different concentrations (1 and 10 mg L⁻¹) of polystyrene nano- and microplastics in the extracellular carbohydrates and in the EPS production was studied. The presence of nano- and microplastics induced a negative effect on the microalgal growth (of up to 47%). The results show that the EPS produced by Cyanothece sp. exhibits high bioflocculant activity in low concentrations. Also, the EPS displayed very favourable characteristics for aggregation, as the aggregates were confirmed to consist of microalga, EPS and both the nano- and microplastics. These results highlight the potential of the microalgal-based biopolymers to replace hazardous synthetic flocculants used in wastewater treatment, while aggregating and flocculating nano- and microplastics, demonstrating to be a multi-purposed, compelling, biocompatible solution to nano- and microplastic pollution.
Afficher plus [+] Moins [-]A review of the potential utilisation of plastic waste as adsorbent for removal of hazardous priority contaminants from aqueous environments
2020
Zhang, Huiyi | Pap, Sabolc | Taggart, Mark A. | Boyd, Kenneth G. | James, Neil A. | Gibb, Stuart W.
There is growing global awareness of the presence and negative impacts of waste plastic in the marine environment. Risks to wildlife include ingestion and entanglement for macro-plastic (larger than 5 mm in length), alongside food chain transfer for micro-plastics (less than 5 mm in length). Plastics in the marine environment have also been shown to adsorb and accumulate contaminants from seawater, e.g., heavy metals and hydrophobic organic compounds. This means that plastics can additionally act as vectors for transport of contaminants, permitting ecotoxicological risks to be spatially extended. However, the ability of waste plastic to adsorb pollutants also offers potential opportunity, if they can be used for the decontamination of wastewater. Here, we provide an overview of marine plastic types and distribution, and then systematically assess their potential to be repurposed as novel adsorbents. Data published in recent years are interrogated to gain an overview of the interaction mechanisms between marine plastics and both organic and inorganic contaminants. In addition, factors that may be exploited to enhance their performance in removal of contaminants are also reviewed and prioritised, e.g., surface modification and activation. This paper highlights the novel potential of repurposing plastic waste for wastewater treatment applications and seeks to identify key knowledge gaps and future research priorities for scientists and engineers.
Afficher plus [+] Moins [-]Influence of dietary iron exposure on trace metal homeostasis and expression of metal transporters during development in zebrafish☆
2020
Chandrapalan, Theanuga | Kwong, Raymond W.M.
The present study investigated the effects of dietary iron (Fe) exposure on physiological performance and homeostatic regulation of trace metals during development (5–28 days post-fertilization; dpf) in zebrafish (Danio rerio). The results demonstrated that whole body Fe content was increased in 14 dpf larvae fed a high Fe diet. Cumulative mortality was also significantly elevated during exposure to the high Fe diet. Using droplet digital PCR, we observed that high Fe-exposed larvae exhibited an increase in mRNA levels of the Fe-storage protein ferritin, which appeared to be associated with the elevated level of whole body Fe content. Further, the results indicated that dietary Fe exposure induced transient changes in the mRNA expression levels of various metal transporters, including the iron transporter dmt1, and the zinc transporters zip8 and zip14. The expression of the epithelial Ca²⁺ channels (i.e., ecac) was also found to increase by high dietary Fe. Overall, our findings suggest that larval fish during the early nutritional transition period are sensitive to the effects of dietary Fe.
Afficher plus [+] Moins [-]Spatial-temporal distribution and transport flux of polycyclic aromatic hydrocarbons in a large hydropower reservoir of Southeast China: Implication for impoundment impacts
2020
Wu, Yuling | Wang, Xinhong | Ya, Miaolei | Li, Yongyu | Liu, Yihao | Chen, Hanzhe
In order to investigate the impacts of dam-related water impoundment on the spatial-temporal variations and transport of anthropogenic organic pollutants, 15 priority polycyclic aromatic hydrocarbons (PAHs) were analyzed in water samples from the Shuikou Reservoir (SKR) of the Minjiang River. The SKR was formed after the construction of the Shuikou Dam, which is the largest hydropower station in Southeast China. The water samples were collected from the backwater zone of the SKR, in both the wet and dry seasons, corresponding to the drainage and impoundment periods of water flow, respectively. The concentrations of the dissolved PAHs in surface water from the wet season (average of 161 ± 97 ng L⁻¹) were significantly higher (ANOVA, p < 0.01) than those from the dry season (average of 43 ± 21 ng L⁻¹). PAH concentrations in the SKR decreased from upstream (industrialized cities) to downstream (rural towns or counties), indicating high PAH loads caused by intensive urbanization effects. The high proportions of 3-ring PAHs in the wet season were from local sources via surface runoff; while the elevated proportions of 4- to 6- ring PAHs in the dry season reflected atmospheric deposition emerged of these PAHs and/or volatilization of 3-ring PAHs enhanced. Molecular diagnostic ratios of PAH isomers in multimedium and principal component analysis indicated that PAH presence in the SKR was mainly attributed to pyrogenic origin. The isomeric ratios of fluoranthene to fluoranthene plus pyrene in the wet season were homogeneous, implying that there were continuous new inputs along the riverine runoff. However, these ratios showed spatial downward trend in the dry season, indicating continued degradation of PAHs occurred along the transport path during the impoundment period. The input and output fluxes of PAHs in the SKR were 5330 kg yr⁻¹ and 2991 kg yr⁻¹, revealing that the reservoir retained contaminants after impoundment of the hydropower dam.
Afficher plus [+] Moins [-]Spatial contrasts in hepatic and biliary PAHs in Tilefish (Lopholatilus chamaeleonticeps) throughout the Gulf of Mexico, with comparison to the Northwest Atlantic
2020
Snyder, Susan M. | Olin, Jill A. | Pulster, Erin L. | Murawski, Steven A.
A multinational demersal longline survey was conducted on the Gulf of Mexico continental shelf over the years 2015 and 2016 to generate a Gulf-wide baseline of polycyclic aromatic hydrocarbon (PAH) concentrations in demersal fishes. Tilefish (Lopholatilus chamaeleonticeps) were sampled in all regions of the Gulf of Mexico for biometrics, bile, and liver. Tilefish liver was also obtained from surveys in the northwest Atlantic Ocean for comparison. Liver tissues (n = 305) were analyzed for PAHs and select alkylated homologs using QuEChERS extractions and gas chromatography tandem mass spectrometry. Bile samples (n = 225) were analyzed for biliary PAH metabolites using high-performance liquid chromatography with fluorescence detection. Spatial comparisons indicate the highest levels of PAH exposure and hepatic accumulation in the north central Gulf of Mexico, with decreasing concentrations moving from the north central Gulf counterclockwise, and an increase on the Yucatán Shelf. Hepatic PAH concentrations were similar between the Gulf of Mexico and the northwest Atlantic, however, Tilefish from the northwest Atlantic had higher concentrations and more frequent detection of carcinogenic high molecular weight PAHs. Overall, results demonstrate that PAH pollution was ubiquitous within the study regions, with recent exposure and hepatic accumulation observed in Tilefish from both the Gulf of Mexico and northwest Atlantic.
Afficher plus [+] Moins [-]Availability of specific prey types impact pied flycatcher (Ficedula hypoleuca) nestling health in a moderately lead contaminated environment in northern Sweden
2020
Lidman, Johan | Jonsson, Micael | Berglund, Åsa M.M.
Anthropogenic metal contamination can cause increased stress in exposed organisms, but it can be difficult to disentangle the anthropogenic influence from natural variation in environmental conditions. In the proximity of a closed lead (Pb)/zinc (Zn) mine in northern Sweden, the health effects of Pb exposure, essential element (calcium [Ca] and Zn) uptake, and prey availability and composition were estimated on pied flycatcher (Ficedula hypoleuca) nestlings, using hemoglobin (Hb) level as a proxy for health. Pb concentration in nestling blood range between 0.00034 and 2.21 μg/g (ww) and nestlings close to the mine had higher Pb concentrations and lower Hb, but contrary to our hypothesis, Hb was not directly related to Pb accumulation. Proportions of flying terrestrial and aquatic insects in available prey and availability of flying terrestrial insects were positively associated with nestling Hb, whereas the proportion of terrestrial ground living prey, the most common prey type, showed a negative association. This suggests that positive influence of certain prey, which does not have to be the most common in the surroundings, can counteract the negative effects from Pb contamination on bird health. Nestlings inhabiting sites adjacent to lakes had an advantage in terms of prey composition and availability of preferred prey, which resulted in higher Hb. As such, our results show that during moderate exposure to metals, variation in natural conditions, such as prey availability, can have great impact on organism health compared to Pb exposure.
Afficher plus [+] Moins [-]F–53B and PFOS treatments skew human embryonic stem cell in vitro cardiac differentiation towards epicardial cells by partly disrupting the WNT signaling pathway
2020
Yang, Renjun | Liu, Shuyu | Liang, Xiaoxing | Yin, Nuoya | Ruan, Ting | Jiang, Linshu | Faiola, Francesco
F–53B and PFOS are two per- and polyfluoroalkyl substances (PFASs) widely utilized in the metal plating industry as mist suppressants. Recent epidemiological studies have linked PFASs to cardiovascular diseases and alterations in heart geometry. However, we still have limited understanding of the effects of F–53B and PFOS on the developing heart. In this study, we employed a human embryonic stem cell (hESC)-based cardiac differentiation system and whole transcriptomics analyses to evaluate the potential developmental cardiac toxicity of F–53B and PFOS. We utilized F–53B and PFOS concentrations of 0.1–60 μM, covering the levels detected in human blood samples. We demonstrated that both F–53B and PFOS inhibited cardiac differentiation and promoted epicardial specification via upregulation of the WNT signaling pathway. Most importantly, the effects of F–53B were more robust than those of PFOS. This was because F–53B treatment disrupted the expression of more genes and led to lower cardiac differentiation efficiency. These findings imply that F–53B may not be a safe replacement for PFOS.
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